Instrument for drawing the curve op circular stair-railings



G. S. STEWART.

Drafting Face Molds for Stairs..

No. 18,110'. l Patented Sept. Jij-1857.

y FaQ/Z UNITED STATES PATENT OFFICE.

GEORGE S. STEWART, OF MEADVILLE, PENNSYLVANIA.

INSTRUMENT FOR DRAWING THE CURVE 0F CIRCULAR STAIR-RAILIN GS.

Suecication of Letters Patent No. 18,110, dated September 1, 1857.

To all 'whom it may concern:

Be it known that I, GEORGE S. STEWART, of Meadville` in the county ofCrawford and State of Pennsylvania, have invented a new and usefulMachine for Drawing Various Kinds of Stair-Rail Patterns, termed bycarpenters Face-Molds; and I do hereby declare that the following is afull and exact description of the same, reference being had to theaccompanying drawings and.

the letters of reference marked thereon.k l

Figure l represents my machine adjusted in worlng order.

H H is the frame of my machine. On the inside of this frame is a groovein each of the pieces H H, as shown at Y. In these grooves the bottomboard W is constructed to slide out and in freely.

A is an upright post, at the inner corner of which a rod S is attachedand tightened or drawn straight by a nut and screw R, the lower end ofthe rod passing through a stirrup and fastened with a head on the endthereof. 'f

O is a radius made to slide freely up and down on the rod S by means ofa hinge U.

Mis a pencil holder constructed so as to slide on the radius O andfastened at any place thereon desired by the set screw N.

B is another post similar to A laid off in inches as shown.

T is an arm made to slide up and down ina mortise in the post B andfastened Where desired by set screw z'. On this arm T (which is alsolaid off in inches) is a rest Z made to move on the arm T and fastenedwhere desired by the set screw Q. See Fig. 2. D is a table on which thepaper is laid for drawing the pattern. This table is hung with thehinges X X to the movable piece E, which moves on the pin L, and is keptin the desired elevation by the semicircle F, and set screw J. Thistable is attached to the bottom piece W W and moves with it, and may beset at any desired distance from the posts A, B.

C1 is a leaf of the table D made to move around a pin V.

Now the manner of working the machine is as follows, to wit: Lay off thehalf of the distance of the outside diameter of the rail from the rod Sto and on the arm T and setthe rest Z at that point; then set the pointof the pencil P to the rest Z, set the top of the index K (which is ofthe same height of the rest Z) to a distance or height Y on the post Bequal to the aggregate height of the risers of the quarter of thecylinder of the stairs; give the piece E the inclination of the stairsby placing the pitch board of the stairs between E and G. This gives thetable D the proper inclination z'. e. the inclination of the stairs.Place the leaf C on the rest Z. The bottom board W is set for use asfollows, to wit: It is made to slide in grooves in H H as may bedesired, and it is so adjusted that when the paper is laid on D, C, thatthe pencil M will scribe the circle desired on the same and for asmaller circle the 'board w is pushed in and for a larger drawn out. Nowlay a piece of paper on the table and leaf D and C, and then move thepencil down on the paper, the radius O moving down the rod S so that thepencil P will rest on the paper, and you have the draft of the facemold; then move the pencil in toward A the distance of the width of therail and draw another line; then lay a rule from the post B to'A anddraw a line and you have the butt joint; then draw another line at rightangles to the posts A and B or parallel to H and you have the lowerjoint, and the pattern is complete. y

What I claim as my invention and desire to secure by Letters Patent, is-

The construction of a machine with an adjustable table D, C, and thegraduated post' B and arm T adjusted with the set screws, Q, z' and thesemicircle F constructed as ldescribed or any other substantially thesame and which will produce the same results.

eno. s. STEWART.

Witnesses:

A. B. RICHMOND, WM. D. TUCKER. R. U. MCENTIRE.

